<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>JSON响应</title>
    <style>
        #result {
            width: 200px;
            height: 100px;
            border: solid 1px red;
        }
    </style>
</head>

<body>
    <div id="result"></div>
    <script>
        const result = document.getElementById('result');
        //绑定鼠标按下事件
        window.onkeydown = function() {
            //发送请求
            const xhr = new XMLHttpRequest();
            //设置响应体数据类型（配合自动转换使用）
            xhr.responseType = 'json';
            //初始化
            xhr.open('GET', 'http://127.0.0.1:8000/json-server');
            //发送
            xhr.send();
            //事件绑定
            xhr.onreadystatechange = function() {
                if (xhr.readyState === 4) {
                    if (xhr.status >= 200 && xhr.status < 300) {
                        //处理服务端返回的结果
                        // console.log(xhr.response);
                        // result.innerHTML = xhr.response;

                        //1、手动对数据转换
                        // let data = JSON.parse(xhr.response);
                        // console.log(data)
                        //result.innerHTML = data.name;

                        //2、自动转换（需要在上面设置响应体类型）
                        console.log(xhr.response);
                        result.innerHTML = xhr.response.name;
                    }
                }
            }
        }
    </script>
</body>

</html>